BBC Russian

18 pages, 5614 KiB

Open AccessArticle

Study on the Multi-Physical Field Simulation of the Double-Glow Plasma Alloying Process Parameters

by Lu Yu, Yiming Wen, Jindong Zhou, Yanzhao Qiu, Danning Yang, Hao Dai, Huilong Zhu, Zhiyuan Hu, Gongtao Liu, Aqib Mashood Khan and Hongyan Wu

Coatings 2024, 14(9), 1175; https://doi.org/10.3390/coatings14091175 - 11 Sep 2024

Abstract

In order to study the coupling mechanism of the process parameters during the double-glow discharge process, and thus to enhance the theoretical study of double-glow plasma surface metallurgical technology, in this paper, a two-dimensional fluid model is established using COMSOL simulation software. The [...] Read more.

In order to study the coupling mechanism of the process parameters during the double-glow discharge process, and thus to enhance the theoretical study of double-glow plasma surface metallurgical technology, in this paper, a two-dimensional fluid model is established using COMSOL simulation software. The effects of key processing factors on the distribution of electrons and excited argon ions, potential and electron temperature in the coupling process of double-glow discharge were investigated. The results indicated that the electron density between the two electrode plates increases as the voltage difference increases. The optimal working pressure was kept between 0.14 Torr and 0.29 Torr. The optimal electrode spacing was between 15 mm and 30 mm and decreased with the increase in pressure. Compared with the actual plasma surface alloying process experiment, the simulation results were consistent with the experiments. The research can guide experiments by combining simulation and theory, and the predictability and accuracy of double-glow surface metallurgy technology have been improved. Full article

(This article belongs to the Special Issue Recent and Future Applications of Coatings for Semiconductors)

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25 pages, 14704 KiB

Open AccessArticle

Improvement of Fatigue Strength in Additively Manufactured Aluminum Alloy AlSi10Mg via Submerged Laser Peening

by Hitoshi Soyama

Coatings 2024, 14(9), 1174; https://doi.org/10.3390/coatings14091174 - 11 Sep 2024

Abstract

As the fatigue properties of as-built components of additively manufactured (AM) metals are considerably weaker than those of wrought metals because of their rougher surface, post-processing is necessary to improve the fatigue properties. To demonstrate the improvement in the fatigue properties of AM [...] Read more.

As the fatigue properties of as-built components of additively manufactured (AM) metals are considerably weaker than those of wrought metals because of their rougher surface, post-processing is necessary to improve the fatigue properties. To demonstrate the improvement in the fatigue properties of AM metals via post-processing methods, the fabrication of AlSi10Mg, i.e., PBF–LS/AlSi10Mg, through powder bed fusion (PBF) using laser sintering (LS) and its treatment via submerged laser peening (SLP), using a fiber laser and/or a Nd/YAG laser, was evaluated via plane bending fatigue tests. In SLP, laser ablation (LA) is generated by a pulsed laser and a bubble is generated after LA, which behaves like a cavitation bubble that is referred to as “laser cavitation (LC)”. In this paper, LA-dominated SLP is referred to as “laser treatment (LT)”, while LC collapse-dominated SLP is referred to as “laser cavitation peening (LCP)”, as the impact of LC collapse is used for peening. It was revealed that SLP using a fiber laser corresponded with LT rather than LCP. It was demonstrated that the fatigue strength at N = 10⁷ was 85 MPa for LCP and 103 MPa for the combined process of blasting (B) + LT + LCP, whereas the fatigue strength of the as-built specimen was 54 MPa. Full article

(This article belongs to the Special Issue Laser Surface Engineering: Technologies and Applications)

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15 pages, 3098 KiB

Open AccessArticle

Development of a Controlled Low-Strength Material Containing Paraffin–Rice Husk Ash Composite Phase Change Material

by Hongfei Xu and Wenting Qu

Coatings 2024, 14(9), 1173; https://doi.org/10.3390/coatings14091173 - 11 Sep 2024

Abstract

In order to reduce heat loss and diffusion of underground heating pipelines, this research incorporated phase change material (PCM) into the controlled low-strength material (CLSM) to prepare a pipeline backfill material with temperature control performance. In response to the problem that PCM leaks [...] Read more.

In order to reduce heat loss and diffusion of underground heating pipelines, this research incorporated phase change material (PCM) into the controlled low-strength material (CLSM) to prepare a pipeline backfill material with temperature control performance. In response to the problem that PCM leaks easily, a new type of paraffin–rice husk ash composite PCM (PR-PCM) was obtained by adsorbing melted paraffin into rice husk ash. Through mixing PR-PCM with dredged sediment (DS) and ordinary Portland cement (OPC), a controlled low-strength material (CLSM) with temperature control performance was prepared. The flowability, mechanical properties, microscopic characteristics, thermal characteristics, and durability of CLSM were analyzed through flowability, unconfined compressive strength (UCS), X-ray diffraction (XRD), scanning electronic microscopy (SEM), differential scanning calorimetry (DSC), and phase change cycle tests. The results show that when water consumption is constant, as the PR-PCM content increases, the flowability of CLSM increases, and the strength decreases. The CLSM has an obvious paraffin diffraction peak in the XRD pattern, and its microstructure is dense with few pores. The melting point of CLSM is 50.65 °C and the latent heat is 4.10 J/g. Compared with CLSM without PR-PCM, the maximum temperature difference during the heating process can reach 3.40 °C, and the heat storage performance is improved by 4.1%. The strength of CLSM increases and the melting point decreases after phase change cycles. CLSM containing PR-PCM has the characteristics of phase change temperature control, which plays a positive role in reducing heat loss by heating pipelines and temperature change in backfill areas. Full article

(This article belongs to the Special Issue Development and Characterization of New Construction Materials and Coatings)

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14 pages, 5783 KiB

Open AccessArticle

Laser-Melted Wc/Ni-Based Coating Remelting Study on Q235 Steel Surface

by Xianglin Wu, Junhao Chen, Jiang Huang, Wenqing Shi, Qingheng Wang, Fenju An and Jingquan Wu

Coatings 2024, 14(9), 1172; https://doi.org/10.3390/coatings14091172 - 11 Sep 2024

Abstract

In order to study the effect of laser remelting on the properties of Q235 steel, WC-enhanced nickel-based remelted layers at different powers were prepared on the surface of Q235 steel using laser cladding technology. Their micro-morphologies were observed using scanning electron microscopy, and [...] Read more.

In order to study the effect of laser remelting on the properties of Q235 steel, WC-enhanced nickel-based remelted layers at different powers were prepared on the surface of Q235 steel using laser cladding technology. Their micro-morphologies were observed using scanning electron microscopy, and their hardness and corrosion resistance were tested using a Vickers hardness tester and an electrochemical workstation. The results show that when the laser power reached 1600 W, the number of WC particles was reduced, the fragments of the broken reinforcement particles were more evenly distributed, the fused layer had the highest uniformity, and the microhardness was more average. Additionally, the corrosion current density reached 2.397 × 10⁻⁵ A/cm², the self-corrosion potential E_corr of the remelted coatings was positive relative to the substrate, the corrosion resistance was the highest, the coating was uniformly flat, and its hardness was the highest. Full article

(This article belongs to the Special Issue Recent Development in Post-processing for Additive Manufacturing)

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19 pages, 11166 KiB

Open AccessArticle

Microstructure and Properties of CoCrFeNiTi_x High-Entropy Alloys Fabricated by Laser Additive Manufacturing

by Kai Wang, Daliang Song, Likun Li, Guanghui Shao, Yingye Mi, Huiping Hu, Chuan Liu and Ping Tan

Coatings 2024, 14(9), 1171; https://doi.org/10.3390/coatings14091171 - 11 Sep 2024

Abstract

CoCrFeNi HEAs have better ductility, while the strength and corrosion resistance need to be further improved, while metal materials for deep-sea operations put forward the requirement of excellent mechanical properties and very high corrosion resistance; however, CoCrFeNi HEAs have been less studied for [...] Read more.

CoCrFeNi HEAs have better ductility, while the strength and corrosion resistance need to be further improved, while metal materials for deep-sea operations put forward the requirement of excellent mechanical properties and very high corrosion resistance; however, CoCrFeNi HEAs have been less studied for the trade-off between mechanical properties and corrosion resistance. Therefore, the present study utilized the laser melting deposition (LMD) technique to fabricate a series of (CoCrFeNi)Ti_x (x = 0.2, 0.4, 0.6, 0.8, 1.0 at.%) HEAs and systematically investigated the influence of Ti content on the alloy’s microstructure, phase composition, mechanical properties, and electrochemical performance. The research findings revealed that as the Ti content increased, the alloy gradually transformed from a single face-centered cubic (FCC) phase to an FCC and body-centered cubic (BCC) dual-phase structure. The addition of Ti induced a transition in the alloy’s microstructure from an equiaxed to a dendritic morphology, accompanied by grain refinement. Energy dispersive spectroscopy analysis confirmed the uniform distribution of Ti within the alloy. The hardness of the alloy increased significantly with the increase in Ti content, reaching 804.5 HV when the Ti content was 1.0 at.%, which was 4.13 times higher than the Ti-free alloy. The tensile and compression test results showed that the (CoCrFeNi)Ti_x alloy with a Ti content of 0.4 at.% exhibited the best overall mechanical performance. The electrochemical test results indicated that the addition of Ti effectively enhanced the corrosion resistance of the alloy, with the 0.4 at.% Ti-containing alloy exhibiting the optimal corrosion resistance. This study provides a strong theoretical and experimental foundation for the design of high-performance CoCrFeNi-based HEAs. Full article

(This article belongs to the Special Issue Manufacturing and Surface Engineering IV)

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10 pages, 2751 KiB

Open AccessArticle

Investigation of the Flow Characteristics of Coated Slag during Continuous Casting

by Guohui Li, Shanjiao Wang and Fengming Du

Coatings 2024, 14(9), 1170; https://doi.org/10.3390/coatings14091170 - 11 Sep 2024

Abstract

During continuous casting, coated slag is applied to molten steel to enhance heat transfer and lubrication. In this study, a numerical calculation model was built to reveal the flowing characteristic of slag according to the fundamental principles of heat transfer and viscous fluid [...] Read more.

During continuous casting, coated slag is applied to molten steel to enhance heat transfer and lubrication. In this study, a numerical calculation model was built to reveal the flowing characteristic of slag according to the fundamental principles of heat transfer and viscous fluid mechanics. The flow and heat transfer behaviour of protective slag on the surface of molten steel and the flow velocity of liquid slag in slag channel gaps were calculated and analyzed. The streaming and thermal conduction situation of slag on the surface of molten steel, as well as the flow velocity of liquid flux in the slag passage gap, were calculated and analyzed. The results showed that as the thickness of the liquidus slag film increased from 10 to 12 mm, the thermal flux density at the top of the flux film layer decreased from 0.1059 to 0.0882 MW/m². The heat flux density increased rapidly within 0.1 m of the narrow side of the mould, reaching a peak value of 2.27 MW/m². As the viscosity temperature factor of the flux increased from 0.45 to 2.05, the maximum floating speed of the liquid film from the water inlet to the narrow side in the centre district of the mould decreased from 0.0316 to 0.028 m/s, representing a reduction of approximately 11.4%. This study can provide a reference for the design and improvement of protective slag. Full article

(This article belongs to the Special Issue Liquid–Fluid Interfaces and Dynamics—2nd Edition)

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16 pages, 13071 KiB

Open AccessArticle

Metallization of Carbon Fiber-Reinforced Plastics (CFRP): Influence of Plasma Pretreatment on Mechanical Properties and Splat Formation of Atmospheric Plasma-Sprayed Aluminum Coatings

by Christian Semmler, Willi Schwan and Andreas Killinger

Coatings 2024, 14(9), 1169; https://doi.org/10.3390/coatings14091169 - 11 Sep 2024

Abstract

Carbon fiber-reinforced plastics (CFRPs) have broad applications as lightweight structural materials due to their remarkable strength-to-weight ratio. Aluminum is often used as a bond coating to ensure adhesion between CFRPs and further coatings with a higher melting temperature. However, challenges persist in optimizing [...] Read more.

Carbon fiber-reinforced plastics (CFRPs) have broad applications as lightweight structural materials due to their remarkable strength-to-weight ratio. Aluminum is often used as a bond coating to ensure adhesion between CFRPs and further coatings with a higher melting temperature. However, challenges persist in optimizing their surface properties and adhesion attributes for diverse applications. This investigation explores the impact of sandblasting and plasma pretreatment on CFRP surfaces and their influence on plasma-sprayed aluminum coatings. Two distinct CFRP substrates, distinguished by their cyanate ester and epoxy resin matrices, and two different aluminum powder feedstocks were employed. Plasma pretreatment induced micro-surface roughening in the range of 0.5 µm and significantly reduced the contact angles on polished specimens. Notably, on sandblasted specimens, plasma-activated surfaces displayed improved wetting behavior, which is attributed to the removal of polymeric fragments and augmented fiber exposure. Aluminum splats show a better interaction with carbon fibers compared to a polymeric matrix material. The impact of plasma activation on the coating adhesion proved relatively limited. All samples with plasma activation had deposition efficiencies that increased by 12.5% to 34.4%. These findings were supported by SEM single-splat analysis and contribute to a deeper comprehension of surface modification strategies tailored to CFRPs. Full article

(This article belongs to the Special Issue Microstructure, Friction and Wear, Hardness Properties and Numerical Simulation of Coatings)

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14 pages, 1255 KiB

Open AccessArticle

Impact of Diamond-like Carbon Films on Reverse Torque: Superior Performance in Implant Abutments with Internal Conical Connections

by Arianne Vallim Pinto Coelho, Viviane Maria Gonçalves de Figueiredo, Leandro Lameirão Ferreira, Alecsandro de Moura Silva, Marcelo Gallo Oliani, José Renato Cavalcanti de Queiroz, Argemiro Soares da Silva Sobrinho, Lafayette Nogueira Junior and Renata Falchete do Prado

Coatings 2024, 14(9), 1168; https://doi.org/10.3390/coatings14091168 - 10 Sep 2024

Abstract

The loosening or fracture of the prosthetic abutment screw is the most frequently reported complication in implant dentistry. Thin diamond-like carbon (DLC) films offer a low friction coefficient and high wear resistance, functioning as a solid lubricant to prevent the weakening of the [...] Read more.

The loosening or fracture of the prosthetic abutment screw is the most frequently reported complication in implant dentistry. Thin diamond-like carbon (DLC) films offer a low friction coefficient and high wear resistance, functioning as a solid lubricant to prevent the weakening of the implant–abutment system. This study evaluated the effects of DLC nanofilms on the reverse torque of prosthetic abutments after simulated chewing. Abutments with 8° and 11° taper connections, with and without DLC or silver-doped DLC coatings, were tested. The films were deposited through the plasma enhanced chemical vapor deposition process. After two million cycles of mechanical loading, reverse torque was measured. Analyses with scanning electron microscopy were conducted on three samples of each group before and after mechanical cycling to verify the adaptation of the abutments. Tribology, Raman and energy-dispersive spectroscopy analyses were performed. All groups showed a reduction in insertion torque, except the DLC-coated 8° abutments, which demonstrated increased reverse torque. The 11° taper groups experienced the most torque loss. The nanofilm had no significant effect on maintaining insertion torque, except for the DLC8 group, which showed improved performance. Full article

(This article belongs to the Special Issue Advances in Surface Engineering and Biocompatible Coatings for Biomedical Applications, 2nd Edition)

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12 pages, 5789 KiB

Open AccessArticle

Mechanical and Microstructural Characterization of AISI 316L Stainless Steel Superficially Modified by Solid Nitriding Technique

by Rene Guardian-Tapia, Isai Rosales-Cadena, Jose Luis Roman-Zubillaga and Sergio Ruben Gonzaga-Segura

Coatings 2024, 14(9), 1167; https://doi.org/10.3390/coatings14091167 - 10 Sep 2024

Abstract

AISI 316L austenitic stainless steel superficially modified by the solid nitriding technique was investigated at different nitriding times (2, 4, 6, 8, 12 and 24 h) and at 450 °C. The microstructural characterization was conducted using scanning electron microscopy (SEM) analysis and X-ray [...] Read more.

AISI 316L austenitic stainless steel superficially modified by the solid nitriding technique was investigated at different nitriding times (2, 4, 6, 8, 12 and 24 h) and at 450 °C. The microstructural characterization was conducted using scanning electron microscopy (SEM) analysis and X-ray diffraction analyses, finding the presence of Fe_2–3N, Fe₄N and Cr₂N, among others. The mechanical behavior of the modified surfaces was carried out by developing hardness profiles and relating it with the nitride layer thickness evaluated using scanning electron microscopy (SEM), obtaining layers up to 70 µm wide. The nitrogen diffusion produced species above and below the surface sample with a transformation from the austenitic phase to an expanded austenite (γ_N) phase, which is responsible for producing an increase in hardness of up to 1200 HV in the samples treated at 24 h, which is four times higher than the untreated steels. Wear evaluations of the obtained layers were performed using a pin-on-disk system under zero lubrication, indicating that the samples with 12 and 24 h of treatment present the best wear resistance promoted by an oxidative–adhesive mechanism. The obtained results are positively comparable with those of the ion nitriding technique but with a lower implementation cost. Full article

(This article belongs to the Special Issue Enhanced Mechanical Properties of Metals by Surface Treatments)

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15 pages, 5343 KiB

Open AccessArticle

Effect of the Atmosphere on the Properties of Aluminum Anodizing

by Gabriela Baltierra-Costeira, Jesús Emilio Camporredondo-Saucedo, Marco Arturo García-Rentería, Lázaro Abdiel Falcón-Franco, Laura Guadalupe Castruita-Ávila and Adrián Moisés García-Lara

Coatings 2024, 14(9), 1166; https://doi.org/10.3390/coatings14091166 - 10 Sep 2024

Abstract

This study aims to quantify the effect of process parameters on the anodizing of Al6061 aluminum. To achieve this, studies on layer thickness, the porosity of the anodized surface, electrochemical techniques, X-ray diffraction, grain size estimation, and statistical analysis were conducted for three [...] Read more.

This study aims to quantify the effect of process parameters on the anodizing of Al6061 aluminum. To achieve this, studies on layer thickness, the porosity of the anodized surface, electrochemical techniques, X-ray diffraction, grain size estimation, and statistical analysis were conducted for three different atmospheres (without air, air, and oxygen). Parameter levels were established as follows: temperature (30 °C, 45 °C, and 60 °C), time (20 min, 40 min, and 60 min), electrolyte concentration (0.5 M), voltage (9 V), and current intensity (0.600 A). A 3³ experimental design (three factors, three levels) was proposed, and mathematical models were obtained using general factorial design. The experimental design was used to determine the three most important variables in the optimal condition. A total of 27 tests were conducted using sulfuric acid electrolytic solutions, of which 12 samples were selected by the factorial design method, which simultaneously evaluates the effects of factors and their interactions in a single experiment. Measurement of porosity and oxide layer thickness was performed using scanning electron microscopy. The purity of the anodic layer formed was characterized using X-ray diffraction techniques with a vertical goniometer X-ray diffractometer. The electrochemical behavior is presented through potentiodynamic polarization curves for the anodic layer. A general factorial design and an analysis of variance (ANOVA) were conducted to establish the significant factors for layer thickness, grain size, and reaction rate. Finally, the best results and their parameters for each response are presented. Full article

(This article belongs to the Special Issue New Functional Coatings and Thin Films for Sensor and Green Energy Technologies)

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18 pages, 5462 KiB

Open AccessArticle

The Effects of Different Ultrasonic Composite Surface Modifications on the Properties of H13 Steel for Shield Tunnel Machine Cutter Ring

by Xiuyu Chen, Yalong Li, Longhui Li, Huanbin Xu, Yi Li, Zhilong Xu, Qingshan Jiang, Shixu Mu, Yin Li and Heng Liu

Coatings 2024, 14(9), 1165; https://doi.org/10.3390/coatings14091165 - 9 Sep 2024

Abstract

Tunnel boring machines (TBMs) are exposed to the impact of the ground shattering force and the friction of sandstone during excavation work, and are prone to wear and breakage, and other failures. Traditional heat treatment processes cannot simultaneously achieve the required high-energy composite [...] Read more.

Tunnel boring machines (TBMs) are exposed to the impact of the ground shattering force and the friction of sandstone during excavation work, and are prone to wear and breakage, and other failures. Traditional heat treatment processes cannot simultaneously achieve the required high-energy composite structure of hard external and tough internal properties for cutter rings, leading to inadequate wear resistance and impact toughness under working conditions. This study utilizes H13 steel as the base material, and based on a study of carburizing, nitriding, and ultrasonic impact processes for H13 steel analyzing the effects of different high-energy composite modification processes on the hardness distribution, microstructure, and residual stress of H13 steel, the mechanisms by which high-energy composite modification processes affect the wear resistance and impact resistance of H13 steel are revealed. The results indicate that the wear amount and impact toughness of the sample subjected to carburizing and ultrasonic surface rolling composite strengthening were 1.9 mg and 27.34 J/cm², demonstrating the best wear and impact resistance. This combination of properties allows the H13 steel cutter ring to achieve the optimal overall performance in terms of wear resistance and impact resistance. Full article

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19 pages, 5805 KiB

Open AccessArticle

Assessment of Warionia saharea Essential Oil as a Green Corrosion Inhibitor for Mild Steel in HCl: Experimental and Computational Studies

by Abdeslam Ansari, Youssef Youssefi, Mohamed Tanghourte, Nazih Ouassou, Nazih Asoufar, Mohamed Znini, Hassane Lgaz, El Houssine Mabrouk, Mohamed Azrour, Han-Seung Lee and Belkheir Hammouti

Coatings 2024, 14(9), 1164; https://doi.org/10.3390/coatings14091164 - 9 Sep 2024

Abstract

The objective of this research work is the study of the inhibitory effect of Warionia saharea essential oil (WSEO) on the corrosion of mild steel (MS) in molar HCl solution, employing both experimental and theoretical methods. This inhibitory effect (IE) has been evaluated [...] Read more.

The objective of this research work is the study of the inhibitory effect of Warionia saharea essential oil (WSEO) on the corrosion of mild steel (MS) in molar HCl solution, employing both experimental and theoretical methods. This inhibitory effect (IE) has been evaluated by using a combination of weight loss measurements (LW) and various electrochemical methods, such as open circuit potential (OCP), potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) experiments. The LW results indicated that IE increased with inhibitor concentration, reaching 83.34% at 3.00 g/L. The PDP analysis suggested that WSEO functions as a mixed inhibitor, while in the EIS results the R_ct values increased with inhibitor concentration to reach 165.8 Ω cm² at 2.00 g/L, suggesting a defensive film formation by WSEO molecules over the metallic surface. The thermodynamic study demonstrated that the WSEO molecules adsorption on the MS surface followed a Langmuir isotherm, involving mixed physical and chemical (physicochemical) adsorption on the MS surface. Theoretical methods, including density functional theory (DFT) and molecular dynamics (MD) simulations, were employed to elucidate the inhibition mechanisms of the three main components of WSEO. The quantum chemical analysis, using density functional theory (DFT) and molecular dynamics (MD) simulations, showed a low ΔE_gap value of 6.30 eV and a low adsorption energy (E_ads) value on an Fe (110) substrate of −258 Kcal/mol for (E)-Nerolidol, indicating the significant contribution of this molecule to the overall corrosion inhibition effect of WSEO. The scanning electron microscope (SEM) analysis verified the presence of a protective film formed by the inhibitor on the MS surface. This study highlights the potential of WSEO as a sustainable and green corrosion inhibitor in acidic environments. Full article

(This article belongs to the Special Issue Surface Science of Degradation and Surface Protection)

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21 pages, 10824 KiB

Open AccessArticle

ULPING-Based Titanium Oxide as a New Cathode Material for Zn-Ion Batteries

by Suben Sri Shiam, Jyotisman Rath, Eduardo Gutiérrez Vera and Amirkianoosh Kiani

Coatings 2024, 14(9), 1163; https://doi.org/10.3390/coatings14091163 - 9 Sep 2024

Abstract

The need for alternative energy storage options beyond lithium-ion batteries is critical due to their high costs, resource scarcity, and environmental concerns. Zinc-ion batteries offer a promising solution, given zinc’s abundance, cost effectiveness, and safety, particularly its compatibility with non-flammable aqueous electrolytes. In [...] Read more.

The need for alternative energy storage options beyond lithium-ion batteries is critical due to their high costs, resource scarcity, and environmental concerns. Zinc-ion batteries offer a promising solution, given zinc’s abundance, cost effectiveness, and safety, particularly its compatibility with non-flammable aqueous electrolytes. In this study, the potential of laser-ablation-based titanium oxide as a novel cathode material for zinc-ion batteries was investigated. The ultra-short laser pulses for in situ nanostructure generation (ULPING) technique was employed to generate nanostructured titanium oxide. This laser ablation process produced highly porous nanostructures, enhancing the electrochemical performance of the electrodes. Zinc and titanium oxide samples were evaluated using two-electrode and three-electrode setups, with cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge–discharge (GCD) techniques. Optimal cathode materials were identified in the Ti-5W (laser ablated twice) and Ti-10W (laser ablated ten times) samples, which demonstrated excellent charge capacity and energy density. The Ti-10W sample exhibited superior long-term performance due to its highly porous nanostructures, improving ion diffusion and electron transport. The potential of laser-ablated titanium oxide as a high-performance cathode material for zinc-ion batteries was highlighted, emphasizing the importance of further research to optimize laser parameters and enhance the stability and scalability of these electrodes. Full article

(This article belongs to the Special Issue Surface Modification of Advanced Transition Metal-Based Materials for Electrochemical Energy Storage)

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9 pages, 1407 KiB

Open AccessArticle

Integration of Self-Assembled Monolayers for Cobalt/Porous Low-k Interconnects

by Yi-Lung Cheng, Joe Kao, Hao-Wei Zhang, Bo-Jie Liao, Giin-Shan Chen and Jau-Shiung Fang

Coatings 2024, 14(9), 1162; https://doi.org/10.3390/coatings14091162 - 9 Sep 2024

Abstract

The integration of self-assembled monolayers (SAM) into cobalt (Co)/porous low-dielectric-constant (low-k) dielectric interconnects is studied in terms of electrical characteristics and reliability in this work. Experimental results indicated that SAM derived from 3-aminopropyltrimethoxysilane (APTMS) improved breakdown field, time-dependent dielectric breakdown, and adhesion for [...] Read more.

The integration of self-assembled monolayers (SAM) into cobalt (Co)/porous low-dielectric-constant (low-k) dielectric interconnects is studied in terms of electrical characteristics and reliability in this work. Experimental results indicated that SAM derived from 3-aminopropyltrimethoxysilane (APTMS) improved breakdown field, time-dependent dielectric breakdown, and adhesion for Co/porous low-k integrated interconnects. However, the improvement magnitude was not large as compared to SAM in the Cu/porous low-k integration. Therefore, the integration of SAM into Co/porous low-k interconnects has a positive effect; however, in order to further promote the efficiency of SAM for Co/porous low-k interconnects, the option of precursors for the growth of SAM is required. Full article

(This article belongs to the Section Surface Engineering for Energy Harvesting, Conversion, and Storage)

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15 pages, 5431 KiB

Open AccessArticle

Synergistic Effect of Elliptic Textures and H-DLC Coatings for Enhancing the Tribological Performance of CuAl10Fe5Ni5 Valve Plate Surfaces

by Mengjiao Wang, Mingbo Zhu, Xinzheng Hu, Kun Liu, Xuefeng Fan, Xiangkai Meng, Xudong Peng and Jinqing Wang

Coatings 2024, 14(9), 1161; https://doi.org/10.3390/coatings14091161 - 9 Sep 2024

Abstract

Axial piston pumps with compact structures and high efficiency are widely used in construction machinery. The efficiency and lifetime strongly depend on the tribological performance of the pump’s valve plate pair. To enhance the tribological performance of the valve plate pair, surface textures, [...] Read more.

Axial piston pumps with compact structures and high efficiency are widely used in construction machinery. The efficiency and lifetime strongly depend on the tribological performance of the pump’s valve plate pair. To enhance the tribological performance of the valve plate pair, surface textures, and H-DLC coatings were fabricated to modify the CuAl10Fe5Ni5 surfaces. The influences of elliptic textures of different sizes and textured H-DLC coatings on the surface friction and wear properties of the valve plate surface under oil lubrication were evaluated using a ring-on-disk tribometer. The results reveal that the friction and wear properties of the CuAl10Fe5Ni5 surfaces are significantly enhanced by elliptic textures, and the friction coefficient and wear rate of textured CuAl10Fe5Ni5 with E90 are maximally decreased by 95% and 87%, respectively. Compared with the surface textures and H-DLC coatings, the textured H-DLC coating has the greatest ability to reduce wear and adhesion. The wear rate of the textured H-DLC coating is further reduced by 98%. This improvement can be explained by the synergistic effect of the elliptic textures and H-DLC coatings, which are attributed to the reduced contact area, debris capture, and secondary lubrication of the elliptic textures, and increased surface hardness. Full article

(This article belongs to the Special Issue Tribological Behavior and Mechanical Performance of Coatings and Materials)

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22 pages, 13071 KiB

Open AccessArticle

Theoretical Calculations and Experimental Study of the Nitrided Layer of 1Cr17Ni2 Steel

by Jiewen Wang, Jun Li, Lina Tang, Taotao Wu, Xin Liu and Yixue Wang

Coatings 2024, 14(9), 1160; https://doi.org/10.3390/coatings14091160 - 9 Sep 2024

Abstract

Due to the harsh operating conditions experienced by 1Cr17Ni2 steel, efforts were made to optimize its performance by subjecting 1Cr17Ni2 stainless steel to nitriding treatments at temperatures of 460 °C, 500 °C, and 550 °C, each for durations of 8 and 16 h. [...] Read more.

Due to the harsh operating conditions experienced by 1Cr17Ni2 steel, efforts were made to optimize its performance by subjecting 1Cr17Ni2 stainless steel to nitriding treatments at temperatures of 460 °C, 500 °C, and 550 °C, each for durations of 8 and 16 h. The formation state of its cross section was observed through a metallurgical microscope and scanning electron microscope, and it was characterized by hardness measurement. Through a ball-on-disk wear experiment, the adhesive wear and friction coefficient of its non-lubricated sliding were measured. The phase composition of its surface was measured by XRD. The results revealed that nitriding led to the formation of a modified layer on the surface of the samples, with a depth of 130 μm after nitriding at 550 °C for 16 h. The hardness of the modified layer exceeded that of the matrix, reaching up to 1400 Hv_0.1. X-ray diffraction (XRD) analysis of the sample surfaces indicated the presence of high-hardness phases such as CrN, γ′-Fe₄N, and ε-Fe_2-3N. This article predicts the mechanical properties of nitrided phases in high-alloy martensitic stainless steel through first-principles computational methods. We provide a reference for improving the performance of high-alloy steel after nitriding through a combination of theoretical calculations and experiments. Full article

(This article belongs to the Special Issue Heat Treatment and Surface Engineering of Tools and Dies)

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10 pages, 1988 KiB

Open AccessArticle

Electrosprayed Chitosan Nanospheres-Based Films: Evaluating the Effect of Molecular Weight on Physicochemical Properties

by Bruna Farias, Francisca Rizzi, Rafael Gerhardt, Eduardo Ribeiro, Daiane Dias, Tito Roberto Cadaval and Luiz Antonio Pinto

Coatings 2024, 14(9), 1159; https://doi.org/10.3390/coatings14091159 - 9 Sep 2024

Abstract

This study explores the effect of chitosan molecular weight on the formation of chitosan-based films by electrospraying process. The oxidative pathway was employed in chitosan with 220.1 kDa to obtain samples with 124.5 and 52.7 kDa. Both samples of depolymerized chitosan resulted in [...] Read more.

This study explores the effect of chitosan molecular weight on the formation of chitosan-based films by electrospraying process. The oxidative pathway was employed in chitosan with 220.1 kDa to obtain samples with 124.5 and 52.7 kDa. Both samples of depolymerized chitosan resulted in spheres within electrosprayed chitosan-based films due to a higher deacetylation degree (~85%). The increase in molecular weight (52.7 to 124.5 kDa) resulted in nanospheres (562 nm) within electrosprayed chitosan-based films, enhancing the surface area-to-volume ratio of the material. The electrospraying process maintained the structural integrity and thermal stability of all chitosan-based films while reducing their crystallinity. These findings highlight the impact of chitosan properties, particularly molecular weight, on the physicochemical characteristics of electrosprayed chitosan-based films. For instance, this work provides insights for the application of electrosprayed chitosan-based films in various fields. Full article

(This article belongs to the Special Issue Advances and Trends in Edible Films and Coatings)

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10 pages, 6434 KiB

Open AccessArticle

Expanded Illite Filler in UV-Curable Polymer Electrolytes for All-Solid-State Li-Ion Batteries

by Minseong Bae, Seongki Ahn, Sunkyung You, Jae-kwang Kim, Daewon Kim, Hanjoo Kim, Hong-Il Kim and Jinjoo Park

Coatings 2024, 14(9), 1158; https://doi.org/10.3390/coatings14091158 - 9 Sep 2024

Abstract

In this study, we explored the potential of illite sourced from Yeongdong-eup, South Korea, as a filler in polymer electrolytes for all-solid-state Li-ion batteries. The illite was expanded (EI) by acid treatment and UV curing was employed to synthesize the polymer electrolytes. The [...] Read more.

In this study, we explored the potential of illite sourced from Yeongdong-eup, South Korea, as a filler in polymer electrolytes for all-solid-state Li-ion batteries. The illite was expanded (EI) by acid treatment and UV curing was employed to synthesize the polymer electrolytes. The Li+ ionic conductivity of the polymer electrolytes was measured at various EI contents, revealing the highest conductivity of 1.08 × 10⁻² S cm⁻¹ at 4 wt% of the EI. The electrochemical performance of NMC cells assembled with the EI-incorporated polymer electrolyte showed a good discharge capacity of over 158.6 mAh g⁻¹ with a coulombic efficiency of 99%. These findings demonstrate the significant potential of EI as a sustainable and efficient filler material for enhancing the performance of polymer-based all-solid-state Li batteries. This study highlighted the applicability of illite sourced from South Korea and its potential contribution to the development of polymer-based all-solid-state batteries. Full article

(This article belongs to the Special Issue Low-Carbon-Footprint Coatings for a Sustainable Future)

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13 pages, 19684 KiB

Open AccessArticle

Microstructure and Tribological Properties of WC/Ni-MoS₂ Titanium-Based Composite Coating on TC4

by Changhao Wang, Xiaohui Yan, Tiangang Zhang, Qiyu Zhang and Zhiqiang Zhang

Coatings 2024, 14(9), 1157; https://doi.org/10.3390/coatings14091157 - 8 Sep 2024

Abstract

To improve the mechanical properties of a TC4 surface, TC4 + Ni-MoS₂ + xWC (x = 5%, 10% and 15% wt.%) composite coatings were prepared by the coaxial feeding laser cladding technique, and the effect of the WC content on the microstructure [...] Read more.

To improve the mechanical properties of a TC4 surface, TC4 + Ni-MoS₂ + xWC (x = 5%, 10% and 15% wt.%) composite coatings were prepared by the coaxial feeding laser cladding technique, and the effect of the WC content on the microstructure and tribological properties of the coatings were investigated using multiple characterization methods. The results indicated that increasing the WC content negatively impacted the forming quality of the coating, but did not change the coating phase which predominantly comprised Ti₂Ni, Ti₂S, TiC, matrix β-Ti and residual WC. With the addition of WC, TiC exhibited an increase in both quantity and particle size, accompanied by a transition in growth morphology from spherical to petal-like. MoS₂ completely dissolved in all coatings and the S element provided by it effectively synthesized a strip-like phase Ti₂S which presented a morphology similar to the lubricating phase TiS in the Ti-based melt pool system. The microhardness and wear-resistance of all the coatings were higher than that of TC4 and gradually improved with the addition of WC, which indicated that raising the WC content was conducive to enhancing the mechanical properties of the coatings. The friction coefficient of TC4 was lower than that of the three WC content coatings, indicating that Ti₂S was not the lubricating phase. The wear mechanism of all coatings was abrasive wear. Full article

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